OK, so I know that other people asked exactly the same... but I just moved from Nouveau to Nvidia using this tutorial, and the new drivers are really, really, really slow. How can I remove Nvidia drivers and recover the open ones?

type sudo apt-get install xserver-xorg-video-nouveau and press Enter - will install this package or tell you if it is already there.

type sudo reboot

This got me back up and running (although no icons in Unity Launcher - since need correct graphic drivers) check system settings to search for Additional drivers to see if this can be addressed - although adding wrong drivers may cause the system to be faulty or freeze after login.

The question is about restoring the open graphics drivers (Nouveau), not about installing nvidia-current. Additionally, sudo stop lightdm won't work. I think you mean sudo service lightdm stop.
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gertvdijkSep 16 '12 at 12:55

1) Isn't nvidia-current the same as Noveau?
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espectalll123Sep 16 '12 at 13:41

2) This is my question AND my answer, so I tested myself the instructions :P
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espectalll123Sep 16 '12 at 13:42